Lab Insights

Mitosis and Cytokinesis: From Theory to Live-Cell Imaging

IntroductionIn our previous article on the cell cycle(see the full article 👉🏻 Click to view), we outlined how cells move through G1, S, G2, and M. This follow-up focuses on the most visibly dynamic steps: Mitosis and Cytokinesis. Mitosis segregates duplicated chromosomes into two nuclei, while cytokinesis divides the cytoplasm and cleaves the plasma membrane to produce two daughter cells. These steps are central to growth, tissue repair, and genomic stability. When these processes fail, they can contribute to disease, including cancer. For the same reason, understanding these processes is crucial for researchers developing anti-mitotic or cytokinesis-modulators. In this post, we walk through each process step by step, explain how control mechanisms and checkpoints coordinate these steps, and share live-cell imaging results of mitotic errors and cytokinesis defects. Table of Contents1. Mitosis- Process and Regulation- Observation Example2. Cytokinesis- Process and Regulation- Observation Example 1. MitosisMitosis is the stage that separates duplicated chromosomes into two nuclei. It prepares the cell for cytokinesis, which divides the cytoplasm and completes cell division. Process and Regulation Mitosis proceeds through five distinct stages—prophase, prometaphase, metaphase, anaphase, and telophase. ProphaseChromosomes condense while centrosomes separate, initiating the formation of the mitotic spindle. PrometaphaseThe nuclear envelope breaks down, and spindle microtubules attach to chromosomes at kinetochores**Kinetochore: the protein complex at the centromere where spindle microtubules attach MetaphaseAll chromosomes line up in the middle of the cell so they are ready to be pulled to opposite sides. AnaphaseSister chromatids separate and move to opposite sides as the spindle pulls on them. TelophaseNew nuclear envelops form around each set of chromosomes, the chromosome decondense, and the cell begins cytokinesis. The spindle assembly checkpoint (SAC) ensures accuracy by monitoring kinetochore–microtubule attachment and tension during prometaphase and metaphase. It keeps the cell at metaphase until all chromosomes are properly attached; only then does anaphase begin. If attachment errors persist, the cell stays arrested and may trigger apoptosis. For the full checkpoint map, see the previous article 👉🏻 Click to view This checkpoint can be activated with small molecules such as nocodazole, which disrupt microtubules and arrest cells in prometaphase to study cell-cycle regulation. Observation Example - Mitosis Arrest Building on the overview above, the following example shows how disrupting spindle attachment alters mitotic progression. Control HeLa cells expressing GFP-H2B condense chromosomes, align them at the metaphase plate, and then separate into two nuclei in sequence. Nocodazole-treated cells fail to form proper attachments to spindle fibers, so they remain arrested in metaphase. Over time, some of these cells lose adhesion or undergo apoptosis. 👉🏻 For detailed information, see the Application Notes Once chromosome are segregated, cytokinesis partitions the cytoplasm and completes cell division. 2.CytokinesisCytokinesis is the final process that completes cell division, during which one cell becomes two daughter cells. Below are the key stages involved in this process. Process and RegulationContractile ring assemblyAt the middle of the cell (the equator), actin and myosin II gather to form a contractile ring. This ring marks the site where the cell will divide.Cleavage furrow ingressionThe contractile ring constricts, and the cell membrane pinches inward to form a visible furrow. AbscissionAt the thin bridge between the two halves (the intercellular bridge, or midbody), the membranes make the final cut, producing two fully separate daughter cells. If the ring cannot form or tighten properly, or if material remains trapped between the two sides, the split may be delayed or fail. When this happens, cells can stay connected or become multinucleated. Observation Example — Cytokinesis Inhibition With the steps and control conditions above in mind, the example below shows how interfering with the contractile ring alters cell division outcome. Control HeLa cells expressing tdTomato-actin form a clear contractile ring, the cleavage furrow ingresses, and abscission completes division into two daughter cells. Cytochalasin B–treated cells show impaired ring formation and weak constriction, so the furrow stalls and division does not finish. Some cells remain connected or become multinucleated. 👉🏻 For detailed information, see the Application Notes In this article, we explored the processes and regulatory mechanisms of Mitosis and Cytokinesis, demonstrating how live-cell imaging makes it possible to observe these events clearly in real time. The results were obtained using Celloger® Mini Plus and Celloger® Pro, which provide consistent and high-quality imaging data to support research. For more details, please visit our homepage and product page. 🧬 Learn more about Celloger® on our product page.

2025-11-28
Inside Curiosis R&D : Building Reliable Research Through Automation

Biological research is becoming increasingly data-driven and automation-focused. As experiments grow more complex, scientists seek tools that ensure precision and reproducibility while simplifying everyday workflows.Curiosis develops technologies that address these needs through laboratory automation and imaging systems. Today, we spoke with Minseop Park, Director of Development, about the team’s approach to product development and the direction behind Curiosis’ latest technologies. Q1. Could you introduce yourself and your role at Curiosis?Director Park: I’m Minseop Park, Director of Development at Curiosis. I lead the Development Division within the R&D Headquarters.Our team manages four main projects—digital pathology, automated colony pickers, beauty and medical devices, and cell counters. I serve as the project manager for the MSP™-320 and CPX™ series, overseeing the entire development process.Q2. What are Curiosis’ main product lines?Director Park: Curiosis develops laboratory automation systems under the slogan ‘Innovative solutions maximizing accuracy and productivity’.Our main lines include digital pathology systems, automated colony pickers, live-cell imaging systems, and cell counting and isolation instruments. Among these, live-cell imaging is one of our key focuses, and the Celloger® series represents this area by enabling continuous cell observation inside the incubator. Q3. What led to the development of the Celloger® series?Director Park: The Celloger® series was created to simplify live-cell imaging and make data acquisition more consistent.Researchers often struggled with imaging cells outside the incubator, as frequent handling could affect their condition. Celloger® solves this by allowing imaging directly inside the incubator, maintaining stable culture conditions throughout observation.It supports both brightfield and fluorescence imaging and is ideal for long-term time-lapse observation. This approach defined Curiosis’ focus on developing reliable and user-friendly research tools.🔗 Learn more about Celloger® Live-Cell Imaging Systems Q4. Which Curiosis technologies or products have received the most positive response globally?Director Park: Among Curiosis’ product lineup, the MSP™-320 digital pathology scanner has received particularly strong global recognition.It was honored with six awards in product and UI design at the world’s three major design competitions. It also won the prestigious R&D 100 Award in the United States.These awards evaluate not only design but also usability, stability, and technological innovation—reflecting the product’s strength in both engineering and user experience. Q5. What was the most meaningful moment for you personally during this process?Director Park: The first international design award we received for the MSP™-320 remains one of the most memorable moments in my career.We went through countless trials to balance UI design with technical perfection, and receiving international recognition made all those efforts worthwhile. Also, when researchers at overseas exhibitions said, ‘This is something I’d use in my own lab right away,’ it gave me confidence that we had built something genuinely valuable for real research settings.🔗 Learn more about MSP™-320 Digital Slide Scanner Q6. Could you introduce the CPX™-α and its main features?Director Park: The CPX™-α is an automated colony picker designed to deliver both precision and speed.It uses a high-resolution camera for XY positioning and an ultrasonic sensor for Z-axis correction. The system maintains high accuracy even on uneven agar surfaces and can process over 3,000 colonies per hour.In addition, the CPX™-α features a fully motorized pin control system, enabling researchers to adjust picking depth precisely to their needs. Its user-friendly software allows easy setup of picking parameters, combining precision with convenience. Our goal was to build a system that offers both high accuracy and operational flexibility, ensuring reliable performance in every experiment. Q7. What makes the CPX™-α stand out in research applications?Director Park: The real value of the CPX™-α lies in how it transforms the research cycle itself.In fields such as synthetic biology and microbiology, the overall research speed depends on how quickly and accurately good colonies can be selected. By reducing manual steps and minimizing variability, the CPX™-α enables researchers to streamline workflows and improve consistency across experiments.This, in turn, helps accelerate the Build–Test–Learn* cycle—allowing scientists to focus more on experiment design and data interpretation rather than repetitive picking tasks. Ultimately, users can experience greater efficiency and confidence in their research outcomes.*Build–Test–Learn: An iterative research process in synthetic biology, where scientists continuously design, test, and refine biological systems.​🔗 Learn more about CPX™-α Automated Colony Picker Q8. What has been the most challenging part of recent development projects?Director Park: One of our biggest challenges is finding effective ways to incorporate AI into our systems.Our instruments process a large volume of image data, so we need to think carefully about how AI can be applied to improve data quality and usability in real research environments. It’s a process that evolves step by step as we keep improving our systems. Q9. How does your team approach these challenges together?Director Park: We address these challenges by setting shared standards and working closely across teams.The development team focuses on creating well-structured and reliable data, while the software team explores practical ways to apply it in future systems. We also collect feedback from users early in the process to ensure that, once AI is introduced, it truly supports researchers in their daily work. Q10. What skills or attitudes do you find most essential in this process?Director Park: Two qualities are most important — a willingness to keep learning and the ability to collaborate.Because AI is evolving rapidly, it’s essential to stay curious and open to new knowledge. At the same time, collaboration is key. Even if someone isn’t developing AI directly, they should think about how their work connects to it.In the end, real progress comes not from individual expertise alone, but from the synergy created when different areas of expertise come together.Q11. What direction is Curiosis pursuing in the global market?Director Park: Curiosis is pursuing global growth through a focused strategy of specialization and differentiation.Rather than following large corporations, we aim to be chosen by researchers through solutions that stand out in our selected segments. In areas such as digital pathology and colony picking, our technology already demonstrates competitiveness on a global level. Building on this strength, we plan to expand step by step into the broader global market with solutions that deliver clear, research-driven value. Q12. What key values do you consider most important in realizing that vision?Director Park: Two values define Curiosis — Curiosity and Focus.Curiosity drives us to question existing methods and search for better answers. Focus allows us to go deep into our chosen fields and build true expertise instead of spreading ourselves too thin.Together, these two values shape how Curiosis approaches innovation and create the foundation for long-term growth. We sincerely thank Director Minseop Park for sharing his time and insights with us. His perspective offered a clear look into how Curiosis’ R&D team approaches innovation.At Curiosis, our goal has always been to create technologies that make research more reliable, efficient, and meaningful. Every development begins with curiosity and grows through collaboration—values that continue to guide our journey.🌱 Explore opportunities to grow with us → Careers at Curiosis

2025-11-04
Cell Cycle Insights with Celloger® : From Theory to Live-Cell Imaging

Cells grow and divide through a tightly regulated process known as the cell cycle. This cycle plays a critical role in tissue development, maintenance, and regeneration, and is essential for repairing damaged structures in living organisms. A clear understanding of cell cycle progression and regulation is crucial for designing and analyzing experiments, and is fundamental in fields such as cancer research, tissue regeneration, and drug efficacy testing. In this article, we outline the key stages and regulatory mechanisms of the cell cycle. We also present observation examples that capture dynamic morphological changes in real time, specifically focusing on mitotic (M phase) progression in two different cell types using live-cell imaging. Table of Contents 1. Phases of the Cell Cycle 2. Cell Cycle Regulation 3. Observation Examples 1. Phases of the Cell CycleThe cell cycle consists of four main stages—G1 (Gap 1), S (Synthesis), G2 (Gap 2), and M (Mitosis)—with some cells entering an additional phase called G0. G1 PhaseThe cell grows and prepares the necessary proteins and energy for DNA synthesis. S PhaseThe cell duplicates its DNA so that each new cell receives an exact copy of genetic information. G2 PhaseThe cell checks for DNA damage and synthesizes additional components needed for mitosis.These three phases (G1, S, G2) are collectively referred to as interphase, during which the cell prepares for division. M PhaseThe duplicated chromosomes are separated, followed by cytokinesis, resulting in two daughter cells.The M phase consists of five substages — prophase, prometaphase, metaphase, anaphase, and telophase — and is the most dynamic and visually distinct phase, especially in live-cell imaging. G0 PhaseSome cells exit the cycle into a quiescent state where they remain metabolically active but non-proliferative.This phase is typical of differentiated cells that no longer need to divide. 2. Cell Cycle RegulationAlthough the cell cycle progresses in a defined sequence, this progression is tightly regulated and not automatic. To ensure genomic stability and accurate division, cells utilize internal checkpoints that monitor readiness before transitioning to the next phase. When errors are detected, these checkpoints function as quality control systems, pausing the cycle to allow for repair. If regulation fails, uncontrolled proliferation may result — a key hallmark of cancer. Key checkpoints include: G1/S CheckpointAssesses whether the cell is ready to enter the S phase. It verifies cell size, nutrient availability, and DNA integrity before allowing DNA replication. If this checkpoint fails, cells with damaged or incomplete DNA may continue dividing, increasing the risk of mutations and cancer development. G2/M CheckpointEnsures that DNA replication is complete and error-free before the cell proceeds to mitosis. Failure at this point can lead to the transmission of genetic errors, contributing to genomic instability. Spindle Assembly CheckpointDuring mitosis, confirms that chromosomes are properly attached to spindle fibers before segregation. Failure at this stage can cause chromosome missegregation and result in aneuploidy. These checkpoints serve as critical safeguards against abnormal cell proliferation. When damage cannot be repaired, the cell cycle halts and apoptosis(programmed cell death) is triggered. 3. Observation Example:To illustrate how U2OS cells progress through the cell cycle in real time, we monitored tFucci(CA)5-transfected cells using the Celloger® Pro. The Fucci system enables clear visualization of phase-specific fluorescence, allowing continuous tracking of individual cells throughout division. U2OS cells expressing the tFucci(CA)5 construct display distinct fluorescence patterns as they move through the cell cycle. Green fluorescence marks S/G2 phases, shifting to yellow as cells enter early mitosis, followed by red fluorescence in G1 after division. Morphological changes such as cell rounding, chromatin condensation, chromosome segregation, and cleavage furrow formation are clearly captured throughout mitosis. These results were acquired using Celloger® Pro, a live-cell imaging system designed to monitor dynamic cellular processes over extended periods.👉 Learn more about Celloger® Pro on our product page. In this article, we explored the phases and regulation of the cell cycle. In addition, we demonstrated how live-cell imaging with Celloger® captures the dynamic morphological changes of cells in real time. Live-cell imaging opens new perspectives in cellular dynamics research. Curiosis provides advanced imaging solutions like Celloger®, supporting researchers in their studies. Learn more about our technology and products on this website.

2025-10-02